The present invention relates to an ink cleaning apparatus, arranged in an inking arrangement, for cleaning an ink from an ink roller at the time of a color change or at the end of a printing operation.
A rotary printing press comprises an inking arrangement for supplying an ink to a machine plate mounted on the outer circumferential surface of a plate cylinder and a dampening arrangement for supplying dampening water. An image formed by the ink and the dampening water supplied from the inking and dampening arrangements and formed on the machine plate is transferred to paper directly or through a blanket cylinder, thereby printing the image. The inking arrangement comprises an ink fountain roller rotated in an ink fountain which stores an ink, a form roller detachably arranged in rolling contact with the machine plate, and vibrating and ink distributing rollers and the like arranged between the ink fountain roller and the form roller. An ink supplied from the ink fountain upon rotation of the ink fountain roller is uniformly distributed in all directions during ink transfer between a large number of ink rollers and is then supplied to the surface of the machine plate by the form roller.
An ink cleaning apparatus for cleaning an ink from the ink roller at the time of a color change or at the end of a printing operation is added to this inking arrangement. A conventional ink cleaning apparatus is arranged as follows. An elongated bucket-like waste liquid container is supported between right and left frames. For example, in this waste liquid container, the sharp distal end of a doctor blade is detachably supported in contact with the outer surface of a vibrating roller as one of a large number of ink rollers. With this arrangement, all the ink rollers are rotated, the distal end portion of the doctor blade is brought into contact with the outer surface of the vibrating roller, and a cleaning solution is dropped downward to the ink rollers manually or by a cleaning solution supply unit. The cleaning solution is then transferred and circulated between the ink rollers to remove the ink. A waste liquid as a mixture of the cleaning solution and the ink is scraped by the doctor blade and is stored in the waste liquid container. Upon cleaning, the doctor blade is separated from the outer surface of the vibrating roller, and the waste liquid attached to the doctor blade is removed. The waste liquid stored in the waste liquid container is treated upon completion of a cleaning operation or periodically during printing.
In this ink cleaning apparatus, however, since the waste liquid scraped by the doctor blade is stored in the waste liquid container, the waste liquid in the waste liquid container must be discharged, or the interior of the waste liquid container must be cleaned so as to prevent the waste liquid from solidification. In addition, the waste liquid attached to the doctor blade and the waste liquid in the waste liquid container are to be discharged, a spilt ink must be manually scraped before it is solidified, thus requiring much labor and a time-consuming operation. As a result, energy savings cannot be achieved, and high operating efficiency of the printing press cannot be obtained.